1. Field of the Invention
This invention relates to method and apparatus for detecting and measuring the magnitude of an impact force applied to a container and more particularly to method and apparatus for simulating a glass container to detect and measure the impact forces to which a bottle is subjected in the filling line.
2. Description of the Prior Art
In a bottle filling line containers, such as glass bottles, are conveyed in virtual contact with one another from station to station at different speeds. At certain points in the filling line the bottle flow stops or is slowed causing impact between adjacent bottles and impact of the bottles with the guide rails that maintain the bottles on the conveying path. Consequently, the bottles experience a variety of impact forces applied at various points along the height of the bottle.
Devices for sensing and recording impact forces delivered to an object are well-known. U.S. Pat. Nos. 4,633,703 and 4,062,221 disclose impact sensing devices that utilize accelerometers for testing the operation of a shock absorber on an automobile. The accelerometer is mounted in a position to detect oscillations of the automobile and provide output signals to circuitry that indicate visually a record of the number of oscillations made by the vehicle. In this manner it is possible to indicate the condition of the shock absorber.
U.S. Pat. No. 3,380,294 discloses an inertial impact instrument used on space vehicles to measure the penetration resistance of the surface of an extraterrestrial body upon impact by a space vehicle. A hollow spherical shell contains three orthogonal decelerometers. The decelerometers are oriented and mounted to measure force components along the X, Y and Z axes. Output from the decelerometers in the form of a pulse signal is fed to oscillators where the signals are amplified and transmitted to an orbiting vehicle above the extraterrestrial body.
U.S. Pat. No. 3,020,875 discloses a device for detecting shocks in any direction in a plane perpendicular to a horizontal axis and in two directions in a plane perpendicular to a vertical axis. The indicator utilizes gauges having weights suspended from a rod which is mounted on a pin of a release mechanism.
U.S. Pat. No. 3,149,606 discloses an accelerometer that includes two weights positioned along different axes. The weights are spring-loaded against supports so that a non-axial acceleration at more than a given value will displace a respective weight from its support. The consequent position of the weight will show that a given acceleration has been exceeded.
While impact devices are known, and in particular impact devices that use accelerometers, none of the known devices disclose method and apparatus adaptable for detecting and measuring impact forces sustained by bottles in a glass filling line. The forces must be effectively measured regardless of the angle of impact. The measuring device must be responsive to a wide range of impact frequencies. Known devices are not readily adaptable to record frequencies of impact that are commonly sustained by bottles in the bottle filling operation. Therefore there is need for bottle testing apparatus capable of recording and measuring impact forces independent of the direction of application and at the frequency range experienced in a bottle filling operation.